proximate causeproximate Ursache (ger.)

Temperature is an environmental proximate cause which has been greatly neglected by laboratory workers, although practical men have long used it to control reproduction in freshwater fishes in aquaria.

Now, if we look over the four causations of the migration of this bird [i.e. the warbler] once more we can readily see that there is an immediate set of causes of the migration, consisting of the physiological condition of the bird interacting with photoperiodicity and drop in temperature. We might call these the proximate causes of migration.

Just as the need for ultimate (in addition to proximate) explanations protects biology from being reduced to molecular biology and finally to chemistry and physics, and as the need for ultimate explanations thus ensures the autonomy of biology, so too it ensures the autonomy of philosophy of biology.